Nekton

Preliminary modeling of tsunami potential in the Tanimbar Islands

Sun, 27 Apr 2025 00:00:00 +0000

The Tanimbar Islands are an area of high tectonic activity and are part of the outer arc island chain formed by subduction in the Banda zone. The presence of the Sorong Fault and Tanimbar Fault around the Tanimbar Islands also affects the level of vulnerability to earthquakes and tsunami hazards. The purpose of this study was to predict the tsunami potential and affected area of the Tanimbar Islands. The method of analyzing the height data and predicting the affected area used COMCOT v1.7 software. Model simulations were performed on the domain layer by using linear equations. Earthquake and fault parameter data were obtained from the USGS website using historical earthquakes dated January 10, 2023. Bathymetry data were obtained from the GEBO website at a resolution of 15-arcsecond (464 m). The model simulation results show that the initial wave height value marked by the red contour is 0.22 m and the lowest low tide value marked by the blue contour is -0.4 m. Based on these results, the tsunami potential in the Tanimbar Islands is not dangerous, as the potentially affected areas in the study area are Selu Island, Woluaru Island, Wotap Island, and Molu Island, as well as the small islands in the western part. The simulation results demonstrate the importance of research related to tsunami hazards that may occur in the future so that appropriate mitigation can be planned for the existence of small islands around the Tanimbar Islands.

Analysis of the suitability and carrying capacity of coral reef ecotourism for diving tourism on Karampuang Island, Mamuju District, West Sulawesi Province

Arwin Arwin, Fanella Muhammad Askin Putra, Jalil Machfud Hapitah — Sun, 04 May 2025 00:00:00 +0000

Nature tourism is a visit to a tourist spot that is still relatively natural, so it is minimal due to disturbance or pollution. The research objective was to analyze the cover condition, damage status of coral reefs, reef fish species diversity, and carrying capacity of the area for diving tourism development in the Karampuang Island Waters. The research was conducted from August 07 to October 07, 2020, in Karampuang Island, Mamuju Regency, West Sulawesi Province. The land suitability analysis used in the research was guided by the formula and matrix of land suitability for diving tourism and analysis of the area's carrying capacity. Based on the calculation of the research results, live coral cover, with an average of 27.26%, was included in the medium category. With a reef fish diversity index found at four stations ranging from 2.97-3.16, with 12 families, 33 species, and 557 individual fish, Karampuang Island is suitable for the development of diving tourism; the entire research area qualifies as marine tourism, especially diving tourism groups with suitability categories between 88.89-100% and the area reaches 52,740 m2 so that it can accommodate as many as 113 tourists per day.

Utilization of shrimp head powder to enhance color performance and growth of multicolor betta fish (Betta splendens)

Tue, 06 May 2025 02:54:28 +0000

Betta splendens is an ornamental fish with a variety of color variations, which is one of the main factors determining its selling value. One of the variants of hippopotamus, which is currently in great demand by ornamental fish enthusiasts, is the multicolor hippopotamus. During maintenance, cupang fish often experience a decrease in color quality caused by internal and external factors. One of the efforts to improve color quality is to supplement the feed with ingredients rich in pigments, such as shrimp head flour (TKU), which contains carotenoids. This study aimed to improve the brightness and color performance of hippopotamus by adding shrimp head meal to commercial feed. The method used was a completely randomized design (CRD) with four treatments, namely, control, 5% TKU, 10% TKU, and 15% TKU, each with three replicates. The research procedure included the preparation of shrimp head meal, mixing feed with TKU, fish rearing, and observation of changes in color brightness, weight and length growth, survival rate, and water quality. The results showed that the utilization of shrimp head meal supplemented into the feed improved the performance of brightness and color patterns in multi-colored cupang fish, including length gain during the treatment, with optimum results shown in the 10% TKU treatment.